The Jargon File (version 4.4.7, 29 Dec 2003):

KLB
 n.

    [common among Perl hackers] Known Lazy Bastard. Used to describe somebody
    who perpetually asks questions which are easily answered by referring to
    the reference material or manual.


The Free On-line Dictionary of Computing (30 December 2018):

Known Lazy Bastard
KLB

    (KLB) A term, used among technical support staff, for
   a user who repeatedly asks for help with problems whose
   solutions are clearly explained in the documentation, and
   persists in doing so after having been told to RTFM.

   KLBs are singled out for special treatment (i.e. ridicule),
   especially if they have been heard to say "It's so boring to
   read the manual!  Why don't you just tell me?".  The deepest
   pit in Hell is reserved for KLBs whose questions reveal total
   ignorance of the basic concepts (e.g., "How do I make a font
   in Excel?", "Where do I turn on my RAM?"), and who refuse
   to accept that their questions are neither simple nor
   well-formed.

   (1998-09-07)